The Germinal Center Response

Ultrastructural anatomy of CALT follicles in the rabbit reveals characteristics of M‐cells, germinal centres and high endothelial venules

“…These events can result in the formation of a bright germinal centre (Wolniak et al 2004) of proliferating lymphocytes as was indeed found here in the rabbit CALT follicles. We found evidence for proliferating lymphoblasts and for FDC that continuously provide antigens on their surface related to the presence of prominent vesicles in their cytoplasm, as observed here and in other lymphoid tissues (Szakal et al 1983), Fig.…”

“…A cell with intermediate density (asterisk) is interposed between dark and bright cells. and considered to support the differentiation of the proliferating lymphoblasts (Wolniak et al 2004). There was also evidence for apoptotic lymphocytes in rabbit CALT GC, which are a typical characteristic of GC because differentiating lymphocytes are induced to die when they exhibit inappropriate antigen specificity or binding affinity.…”

The prostate‐associated lymphoid tissue (PALT) is linked to the expression of homing chemokines CXCL13 and CCL21

“…GC proliferation is indicative of ongoing humoral Ab production [18]. It was revealed by Ki-67 positivity of GC B cells in both PALT and tonsil ( Fig.…”

Cooperation between platelet-derived CD154 and CD4+ T cells for enhanced germinal center formation

“…It is well established that CD4 ϩ T cell CD154 is required for germinal center (GC) formation and production of appreciable levels of switched antibody isotypes (reviewed in ref. [1]). The current paradigm for antibody production proposes that T cells first expand in the T cell zone and then migrate toward the follicle border, where antigen-stimulated B cells have also localized.…”